1. Field of the Invention
The present invention relates to a support apparatus and a support system.
Certain embodiments of the present invention are concerned with improving the arrangement described in Brazil Patent No. PI78 05402 issued on Apr. 26, 1986, to the present inventor. This Brazilian patent relates to a roof covering which uses convex flexible sheets, the edges of which are received in grooves. The center point of the convex shape rests on a horizontal base.
According to a first aspect of the present invention, there is provided a support apparatus including lengthwise beams coupled together by a plurality of first members. The beams are coupled to the first members in such a manner that the beams are pantographically displaceable, thereby reducing the volume of the support apparatus.
The reduction in volume facilitates transportation of the support apparatus to the site where it is required, whereafter the apparatus can be expanded for use.
The expression "pantographically" displaceable or movable used in this specification means that the lengthwise beams can move relative to each other like the two opposite sides of a parallelogram having pivot joints.
According to a second aspect of the invention there is provided a support system including two support apparatus as described above. Each apparatus is arranged with its lengthwise beams parallel to one another and the system includes cross members which secure the two apparatus together. Preferably, arcuate supports extend between the two apparatus and support a cover.
Using this support apparatus, the cover can be provided at the work place economically, since the apparatus is quick and easy to assemble and disassemble. The cover, which may constitute a roof and may be a flexible plate of, e.g., metal or the like, may be arcuately supported by this arrangement.
Preferably at least one of said arcuate supports has an extended end portion which is foldable over the edge of said cover to hold the cover in place.
Thus, the cover can be fixed without screws or similar fastenings so that thermal expansion can take place without warping or stressing of the cover. This is because relative movement between the cover and the arcuate supports is possible while still retaining the cover substantially in place. Lateral movement of the cover is restricted by the folded end portions of the arcuate supports and no separate lengthwise fastening is required.
Thus, according to a further aspect, the invention provides a support system including two longitudinally extending support apparatus laterally spaced from each other, a plurality of longitudinally spaced traverse supports extending between the two apparatus, and a cover carried by the transverse supports, the transverse supports having end portions which are bent over the edges of the cover to hold the cover in place. The transverse supports are preferably arcuate.
Other features and advantages of the present invention will be apparent from the following description taken in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the figures thereof.